DLAQGE(3)

💖 NAME 💖

okay bestie, this is DLAQGE(3) from the Library Functions Manual — and the full source path is a whole journey: /home/abuild/rpmbuild/BUILD/lapack-static-3.12.0-build/lapack-3.12.0/SRC/dlaqge.f. The header/footer shorthand is /home/abui...RC/dlaqge.f(3), and yes, it’s giving Fortran library routine energy. 🫶

✨ SYNOPSIS ✨

Functions/Subroutines

• subroutine DLAQGE (m, n, a, lda, r, c, rowcnd, colcnd, amax, equed) — literally scales a general rectangular matrix, using row and column scaling factors computed by sgeequ. slay. 💅

🛠️ Function/Subroutine Documentation 🛠️

subroutine DLAQGE

   subroutine DLAQGE (integer m, integer n, double precision, dimension( lda, *
       ) a, integer lda, double precision, dimension( * ) r, double precision,
       dimension( * ) c, double precision rowcnd, double precision colcnd,
       double precision amax, character equed)

Same vibe as the synopsis, bestie: DLAQGE scales a general rectangular matrix, using row and column scaling factors computed by sgeequ. 💫

🎯 Purpose

DLAQGE equilibrates a general M by N matrix A using the row and column scaling factors in the vectors R and C. That’s the whole main-character mission. 👑

🧮 Parameters

• M — M is INTEGER; the number of rows of the matrix A. Constraint: M >= 0. ✨
• N — N is INTEGER; the number of columns of the matrix A. Constraint: N >= 0. 🌸
• A — A is DOUBLE PRECISION array, dimension (LDA,N). On entry, the M by N matrix A. On exit, the equilibrated matrix. See EQUED for the form of the equilibrated matrix. 💅
• LDA — LDA is INTEGER; the leading dimension of the array A. Constraint: LDA >= max(M,1). 🫶
• R — R is DOUBLE PRECISION array, dimension (M); the row scale factors for A. 🌈
• C — C is DOUBLE PRECISION array, dimension (N); the column scale factors for A. 🦋
• ROWCND — ROWCND is DOUBLE PRECISION; ratio of the smallest R(i) to the largest R(i). 🔥
• COLCND — COLCND is DOUBLE PRECISION; ratio of the smallest C(i) to the largest C(i). 🔥
• AMAX — AMAX is DOUBLE PRECISION; absolute value of largest matrix entry. ⭐
• EQUED — EQUED is CHARACTER*1; specifies the form of equilibration that was done.
  • = 'N': No equilibration.
  • = 'R': Row equilibration, i.e., A has been premultiplied by diag(R).
  • = 'C': Column equilibration, i.e., A has been postmultiplied by diag(C).
  • = 'B': Both row and column equilibration, i.e., A has been replaced by diag(R) * A * diag(C).

💡 bestie, EQUED is the receipts: it tells you which scaling actually happened. no cap. 💀

🔍 Internal Parameters

These are the internal threshold besties — they run the vibe check on whether scaling happens:

• THRESH — threshold value used to decide if row or column scaling should be done based on the ratio of the row or column scaling factors. If ROWCND < THRESH, row scaling is done, and if COLCND < THRESH, column scaling is done. 🌟
• LARGE and SMALL — threshold values used to decide if row scaling should be done based on the absolute size of the largest matrix element. If AMAX > LARGE or AMAX < SMALL, row scaling is done. 🌈

👑 Author

• Univ. of Tennessee
• Univ. of California Berkeley
• Univ. of Colorado Denver
• NAG Ltd.

Definition at line 140 of file dlaqge.f. 📍

🤖 Author

Generated automatically by Doxygen for LAPACK from the source code. 💻✨

---

okay bestie, that’s the whole page. The footer/source vibe is LAPACK Version 3.12.0 and /home/abui...RC/dlaqge.f(3) — date: not listed, so no date to gatekeep. mwah 💋🫶